Reporting from Sacramento and Los Angeles — Approval for the first of what could be at least a dozen large solar energy projects planned for the high desert near the Los Angeles-Kern County line is under threat from an unlikely source: the military industry.

Northrop Grumman Corp. contends that a proposed 230-megawatt plant near Rosamond to be built by First Solar Inc. could impair operations at a sensitive installation for testing radar-evading stealth technology on aircraft.

Gov. Arnold Schwarzenegger and other supporters fear that if Northrop succeeds in blocking the project, the state would be hobbled in its efforts to create tens of thousands of green-tech jobs and fight global warming by building renewable power plants in the sun-drenched desert of Southern California.

"It is important that this project move forward, not only for Los Angeles County, but in order to achieve the policy objectives of the state of California," Schwarzenegger wrote Monday to the Los Angeles County Board of Supervisors.

Sen. Dianne Feinstein (D-Calif.) said she has offered to host a meeting with officials from the Pentagon, First Solar and Northrop to ensure that the Antelope Valley

solar projects remain on track.

Northrop Chief Executive Officer Wes Bush, she said, told her he would personally try to resolve the matter.

At a meeting Tuesday, the Los Angeles County Board of Supervisors will consider Northrop's appeal of the project's tentative approval.

The project, called AV Solar Ranch One, got preliminary approval Sept. 15 from the Los Angeles County Planning Commission. Developers hope to break ground at the 2,100-acre Antelope Valley site by the end of the year, a deadline to qualify for millions of dollars in a federal economic stimulus subsidy.

But Northrop Grumman wants a delay, perhaps into next year.

The Century City company filed its appeal to gain more time to determine how Solar Ranch One might affect Northrop's testing program, spokesman Jim Hart said.

"We're still studying our options," he said.

At the 1,400-acre Northrop site on the edge of the Tehachapi Mountains, where 15 people are employed, the company bounces radar waves off simulated aircraft on rotating pedestals to determine whether the planes can be detected.

Solar Ranch One is expected to employ 400 construction workers in the economically hard-hit region. Once completed in 2013, it would be the largest solar generating plant using photovoltaic panels to convert sunlight to electricity, executives at the Tempe, Ariz., developer said.

Pacific Gas & Electric Co. has signed a 25-year contract to buy Solar Ranch One's output, which would be enough electricity to power 75,000 average homes.

The solar project has won solid support from local Antelope Valley officials, First Solar Vice President Jim Woodruff said.

"We've had hundreds of meetings on the ground with agencies, residents and environmental groups," he said. "It's had very broad acceptance, not the least of which because of the jobs" it would create.

First Solar said it hired an independent consultant, which determined that construction and operation of the solar plant "will not have a significant effect" on Northrop's testing center.

Los Angeles County's lawyers have a similar view.

"The appeal does not have merit," said Lawrence Hafetz, the principal deputy counsel. And, he said, the Defense Department concurs, dismissing the conflict as "a private matter."

The dispute over Solar Ranch One is the latest controversy involving efforts to build renewable energy projects in the desert, where environmentalists are concerned with protecting habitat for such threatened animals as the desert tortoise and the flat-tailed horned lizard.

BrightSource Energy Inc. in Oakland had to scrap plans last year for a solar facility in the Mojave Desert after clashing with Feinstein, who wanted to declare the area a national monument.

Since then, the company broke ground on a 370-megawatt solar thermal installation located in the Ivanpah Valley.

Northrop raised the same radar-interference issue over the 200-megawatt Rosamond Solar project in Antelope Valley, but the Kern County Board of Supervisors approved the development earlier this month.

Missing out on an opportunity to create jobs would be a travesty, Lancaster Mayor R. Rex Parris said.

Parris is looking to clean-tech investments to ease his city's 17% unemployment rate.

But Parris also recognizes that the aerospace industry long has been a mainstay of the high-desert economy.

"The last thing we want to do is threaten the aircraft industry out here," he said. "We're going to side with Northrop no matter what, because that's where the jobs have been. We want to do whatever we can to keep Northrop here."

Ongoing disputes over permitting and regulatory uncertainty create roadblocks that could discourage renewable energy investors and developers from doing business in California, said Jonathan Kim, who tracks power companies for the Royal Bank of Scotland.

"The bottom line is, renewable energy is too important to the economy and the power market to not vet every potential solution," he said.

"If California has all these regulatory issues, developers are just going to migrate," Kim said. "You could be forfeiting a very promising economic boom."